Rotary swivel



A N 112, 1933. W. D." DAVIDSON ET AL 2,113,647

ROTARY SWIVEL Filed Jan. 13, 1936 3 Shets-Sheet J [/v 7095 MM. L 04M 0.0A woso/v GUGL/ELMO TREMOLA DA Md W 'April 12, 1193:. w. D. DAVID-SON ETA ROTARY SWI VEL Filed Jan. 13, 1936 3 Sheets-Sheet 2 JA/VENTO W/LL/AMD. DAl/Y o/v GUGL/ELMO 7725 LADA A rromve v April 1E2, 193%. w. D.DAVIDSON ET AL ROTARY SWIVEL Filed Jan. 13, 1936' 5 Sheets-Sheet 5Patented Apr. 12, 1938 UNITED STATES ROTARY sr.

Application January 13, 1936, Serial No. 581568 1% Claims.

Our invention relates to rotary swivels which have a particular utilityin the oil producing industry. In the detailed description which is tofollow, our invention will be described in con- 5 nection with such use.

In order that the features and advantages of our invention may be betterunderstood brief reference will be made to the oil producing lndustry.

As illustrated in Fig. l of the accompanying drawings, which shows autility view illustrating the use of our invention, it is commonpractice to drill oil wells by means of a rotary bit I l secured to thelower end of a string of drill pipe l 2. The

drill pipe l2 extends to the surface of the ground and has a kelly itconnected to its upper end which extends through a rotary machine l5 andis engaged and caused to rotate by the table It.

In accordance with standard practice, aswivel ll,

to which type of apparatus our invention relates,

is connected to the upper end of the kelly Hi.

This swivel is supported by means of a travelling block Hi, the hook ofwhich is illustrated in Fig. 1.

During drilling operations it is common practice to pump rotary muddownward through the drill pipe, which rotary mud issues from openingssuch as indicated at 20 in the bit H, and this rotary mud thereafterflows upward through the well to the surface of the ground and performsthe valuable functions of carrying the cuttings to the surface of theground, preventing cave-ins of the walls of the well, and when an oilformation or gas formation is penetrated in holding back the pressure.This rotary mud is pumped by means of a slush pump 2i and flows througha stand pipe 22 and a flexible hose 23 to the swivel H.

In the present advance stage of oil well drilling, wells are drilledvery deep, it being common practice to reach 8000 and 9000 feet, and itis therefore necessary that the swivel be constructed to supportenormous loads. It is likewise necessary to pump the rotary mud underrelatively high pressures. Due to the fact that this rotary mudcontains, as a large percentage of its volume,

abrasive particles, the parts of the swivel must be designed so that anyparts which wear can be easily replaced and so that suitable packing ofrelatively long life, and which may be readily replaced, is provided. Itis furthermore desirable from the standpoint of efiiciency that theswivel be designed so that in case repair is necessary the parts may bequickly taken apart, the repair or replacement work done, and thenquickly assembled, in order thatthe well will not be taken out ofservice for any more than a minimum length of time.

It is the principal object of our invention to provide a swivel which isdesigned from the standpoint of construction and also of operation to 5meet the present and future requirements of the oil drilling industry.

It is an object of our invention to provide a rotary swivel in. whichthe different bearings which support the rotating parts may be readily1o removed, repaired, and replaced in a minimum length of time.

It is an object of our invention to provide a rotary swivel in which thebearings will be provided with ample and eflicient lubrication. 15

It is an object of our invention to provide a rotary swivel inwhich thestuffing box between the stationary and moving parts is so supportedthat it may be readily removed, repaired, and reinstalled. go

It is an object of our invention to provide a rotary swivel in which thestuffing box between stationary and moving parts is so positioned thatit will be efliciently cooled, thus increasing the life of the packing.25

It is an object of our invention to provide a rotary swivel in which thewash pipe which c0- operates with the stumng box and which is ordinarilysubjected to considerable wear may be readily and quickly replaced, thuskeeping the 30 rotary swivel out of service for but a minimum of time.

The foregoing objects set forth the more general and comprehensiveobjects and advantages of the invention. There are, however, manyfeatures and objects which reside in certain preferred details ofconstruction and arrangements of parts and which are too numerous to setforth at this point, but 'will be pointed. out in the course of thedetailed description of our invention which 40 is to follow.

Referring to the accompanying drawings which show preferred andalternative forms of our invention:

Fig. 1 is a utility view (which has already been 45 described)illustrating the utility of our invention.

Fig. 2 is an elevational view partly in section showing the preferredform of our invention.

Fig. 3 is a sectional view taken on the line 3- -3 50 of Fig- 2.

Fig. 4 is a sectional view taken on the line fl--:l of Fig. 2.

Fig. 5 is a fragmentary elevational sectional view taken on the line 5-5of Fig. 2. 55

Fig. 6 is a fragmentary vertical sectional view through the stuffing boxof our invention and is taken on the line 65 of Fig. 3.

Fig. 7 is a fragmentary perspective view of a lantern or spacer partemployed in the stumng box of our invention.

Fig. 8 is afragmentary view similar to Fig. 6, and showing analternative packing arrangement which may be employed in our invention.

Referring to the drawings in detail, and particularly to Figs. 2 to 5inclusive, we provide the swivel I! with a body consisting of an uppersection 30 and a lower section 3 l. The upper section 39 consistsessentially of a cylindrical portion 32 having an outwardly extendingflange 33. The lower section 3i is essentially of cup shape having alower wall 34, a side Wall 35, and an upper flange which engages theflange 33 on the upper section 33. These two parts are. secured togetherby bolts 3'! which extend through openings provided in the flanges 33and 35 and. in the bottom wall These bolts have nuts 3% on the lowerends thereof and thereafter the two sections 38 and 35 may be separatedby removing the nuts 38 from the bolts 3'71. The swivel is supported bymeans of a stirrup or yoke dii which is pivotally mounted on pins 4|secured to the upper section 313.

Rotatably supported within the body is a spindle 43, the lower end ofwhich is connected to the kelly 54. The spindle 13 is rotatablysupported by a bearing arrangement which will now be described. Forcarrying the weight of the spring of drill pipe there is provided athrust bearing M. This thrust bearing is supported by the lower section35 of the body which has a horizontal face d5 on which the thrustbearing rests and has a cylindrical concentric shoulder #55 which holdsthe thrust bearing in a concentric position. The spindle 53 has anoutwardly extending shoulder 48 which engages the thrust bearing 4 andby means of which the weight of the drill pipe is transferred to thethrust bearing.

For the purpose of restraining the spindle 43 from radial or lateralmovement, a lower radial bearing 53, and an upper radial bearing 5| areprovided. The lower radial bearing surrounds a cylindrical face 53 ofthe spindle 53 and engages an inner cylindrical face 54 provided in thelower part of the upper section 33. There is a shoulder 55 on thespindle 43 below the cylindrical face 53 and there is a shoulder 56above the cylindrical face 54 of the section 38. The upper radialbearing surrounds a cylindrical face 59 provided by the spindle 43 andengages an internal cylindrical face 60 provided at the upper end of thesection 30. There is a shoulder 6| provided by the upper section.38 atthe lower end of the internal cylindrical face 68. To prevent relativevertical movement between the spindle 43 and the body we provide ahold-down bearing 63 which is positioned between the shoulder 48 and ashoulder 64 provided by the upper section 30 immediately below theinternal cylindrical face 54. g

The bearings 44, 50, and 63 are all removable from the lower part of thebody and the bearing 5| is removable from the upper part thereof. Thisparticular arrangement of the bearing enables the upper section 30 to berelatively reduced in size and at the same time amply strong. andenables the rotary swivel as a whole to be made considerably smallerthan the swivels in use at the time our invention was developed.

A seal is formed around the lower end of the spindle 43 by means of alower cover 36 which is secured to the lower section 3| and whichcarries suitable oil seal parts 61. A seal is formed at the upper end ofthe spindle 43 by means of a swivel body cover 58 secured to the uppersection 38 by studs 69, and which carries a suitable oil seal member l0.

The body is designed so that it may contain ample lubricant for thevarious bearings. The upper section is provided with an opening throughit which is of sufficient size to receive the spindle 43 and at the sametime provide an oil chamber 12 which carries ample lubrication for theradial bearings 50 and 5|. The lower section 3| is cup shaped, aspointed out heretofore. It therefore provides a relatively large chamber13 which carries a larger volume of lubricant so that the thrust bearingwhich carries the weight of the drill pipe may receive its proper amountof lubrication. The lubricant is delivered to the chambers l2 and 13which cooperate to provide the lubricant chamber of the swivel through apassage 14 which is formed in thecylindrical wall 32 of the uppersection 30. The lower end of the passage 74 is connected to the chamber33, and the upper end thereof is connected to an opening 15 formed inthe swivel body cover $8 and which is closed by a suitable plug l5. Thisfilling passage is extended relatively high in order that the oil levelmay be maintained above the upper radial bearing 5|.

The chamber 13 is designed so that the thrust bearing did is at theinner part thereof. When the parts are in operation the centrifugalforce tends to throw the oil outwardly. It will be noted, however, thatthe chamber 13 is provided with an annular pocket 18 which is below themoving parts of the thrust bearing 44. As shown in Fig. 4, the chamber13 is divided into sections by means of the inwardly extending webs i9and the walls 38 which define the passages through which the bolts 31extend. The pocket i8 which is thus divided into sections provides asediment receptacle into which any sediment or foreign matter in the oilmay settle out of circulation and not be, returned to the bearings. Whenthe lower section has been removed from the upper section the interiorof the chamber 13 is readily accessible and the pocket 18 may at thattime be cleaned.

Secured to the upper end of the spindle 43 is a wash pipe 85. The washpipe has a lower end 86 which extends into a counterbore of the spindle,and it also has a flange 81 through which a securing stud 88 extends.The wash pipe 85 therefore is secured to the spindle 43 and rotatestherewith. The wash pipe 85 is at its upper end in communication with agooseneck 90 and to prevent leakage between the rotating wash pipe 85and the non-rotating gooseneck 90 a stuillng box 9| is provided.

Extended upward from the swivel body cover 68 is a plurality of arms 92which supports a ring 93 at the upper end. The arms 92 and the ring 83constitute what we term a bridge". best shown in Fig. 6, the ring 93 hasa central opening 95 and a counterbore 96. Supported by the ring 93 is astuffing box housing 91. The stufling box housing 91 has a flange 98 atits upper end which rests in the counterbore 96 and has a cylindricalwall ,99 immediately therebelow I00 through which securing studs llllextend. 75

The engagement of the faces forming the depressions I with the studs IOIprevents the stufling box housing from rotating. The lower end of thestufiing box housing is provided with heat radiating fins I03. Thegooseneck'90 has a flange I 04 which rests above the ring 93 and engagesthe upper end of the stufling box housing 91. The studs IOI extendthrough openings in the flange I04 and the parts are secured together bynuts I05 screwed onto the upper ends of the studs. When it is desired todisassemble the stufiing box arrangement the nuts I05 are removed, thegooseneck is removed by moving it upward, and thereafter the stuffingbox housing may be removed bypulling it upward through the opening 95.This exposes the wash pipe 85 and permits its removal. It will'be seenthat these parts may be disassembled and assembled without disturbingthe spindleor body of the rotating swivel. Other than described, thegooseneck 90 is made in accordance with standard practice and the rotaryhose 23 is connected thereto as shown in Fig. l.

In the preferred form of our invention we employ a packing arrangementas illustrated in Fig. 6. An alternative form of packing which may beused is illustrated in Fig. 8.

Referring to Fig. 6, the stuffing box housing 91 is of larger internaldiameter than the external diameter of the wash pipe 85. The lower endof the stuflingbox housing 9?, however, has an inwardly extending wallIN. The flange Hi l of the gooseneck 90 is provided with a passage ofsubstantially the same diameter as the space provided within thestuffing box housing 91 and at the upper end thereof there is a shoulderI09. There is therefore provided around the upper end of the wash pipe85 a packing chamber I09 in which the preferred form of packing of ourinvention is placed.

The upper face of the inwardly extending wall I0? is provided with anannular channel IIIl, which channel has downwardly converging walls vwhich blend into a curved bottom wall. Placed in the packing chamberimmediately above the inwardly extending wall I01 and extending into thechannel I I0 is a packing element I II which is completely annular orring shaped and which is of V-shaped or chevron shaped cross-section.The packing element has a pair of upwardly diverging walls II2 whichhave end faces II I which are substantially of cylindrical shape so thatthe end walls III engage the outer wall of the wash pipe 85'and theinner wall of the stuffing box housing 97. Placed above the packingelement I II is a spacer or lantern IIB. As shown best in Fig. '7, thespacer II6 has a lower annular part of V-shaped cross-section III whichfits against the upper faces of the walls I I2 and has an upper annularportion II8 which provides an upwardly exposed channel I I9 which is ofsubstantially the same shape as the channel H0. The portions I I 1 and II8 are connected together by a relatively thin vertical wall I havingopenings I2I therein.

- The upper section I I8 has vertical channels I23 cut in the oppositesides thereof to permit free passage of grease. Placed above the spacerII 6 is a plurality of packing elements I26 which are of the sameconstruction as packing element III. Placed above the packing elementsI26 is a spacer or lantern I21 which is of the same construction as thespacer or lantern IIB. Placed above the spacer I2! is a pluralityofpacking elements I29, each of which is of the same construction as thepacking elements I II and I26. Placed above the packing elements I29 isa follower I30 which is of V-shaped cross-section at its lower end sothat it fits in between the walls of the uppermost packing element I29tending to hold it against the walls defining the packing chamber I09.Compressed between the follower I30 and the shoulder I08 is a spring I32. The purpose of this spring I32 is to force the entire packingconstruction starting with the follower I30 vdownward against theinwardly projecting wall I 01 in order that the packing elements will beheld in proper packing position; namely, with theend faces I Id of theside walls II2 of the packing elements III, I26, and I29 in engagementwith the two cylindrical surfaces defining the side walls of the packingchamber I09. Adjacent the spacer M0 and the spacer IZ'I grease passagesI35 and I33, respectively, are provided in the stumng box housing III.Suitable grease nipples, such as Alemite fixtures I3? and I30, arescrewed into the passages I35 and I30 so that grease may be introducedbut will be prevented from leaking from the stuffing box. It will beseen that the passages I35 and I30 communicate with grease pockets I00and III provided by the spacers M0 and I27. When grease is introducedinto the upper grease pocket III the pocket is first filled andthereafter grease will flow upwardly around and between the packingelements I29. The pressure, however, of the grease tends to force thepacking elements I26 outwardly so that grease will not flow in adownward direction. When grease is forced into the lower pocket M0 thepocket is first filled and thereafter the grease is forced upwardlyaround the packing elements I26. It will be seen, therefore, that all ofthe space within the packing chamber I09 with the exception of thatoccupied by the various elements which have been described is filledwith grease or other suitable lubricant which may be desired. The springI32 holds the parts in proper operating position and performs itsfunction until the rotary swivel is put into operation. When the slushpump 2I, as shown in Fig. l, is set into operation pressure is developedin the gooseneck 90 and the wash pipe 65. R0- tary mud under pressuremay flow through a small passage I95 into the upper end of the packingchamber I 09 and press against the follower I39. It will therefore beseen that as the pressure of the rotary mud increases the forceexpanding the packing elements also increases. This increase in force isin direct proportion to the pressure of the rotary mud, and thereforewhen higher sealing characteristics are required they are automaticallyobtained. The pressure of the rotary mud may range between 1000 and20,000 pounds.

As stated heretofore, the stufiing box body is provided with heatradiating fins, and therefore the temperature within the stuifing boxwill be maintained at a minimum. The packing may be replenished withgrease at any time desired either during the operation of the rotaryswivel or while it is out of service. This is possible due to the factthat the grease nipples I31 and I38 are mounted on a stationary part.The packing per se of the preferred form of our invention has beenextensively used in the field and has proven to be highly satisfactoryand of much longer life than those of the prior art. Even though wearoccurs in the packing elements III, I26, and I29, a seal is stillmaintained. This is due to the fact that the wear occurs at the facesII4 which engage the rotating wash pipe 85, and as this wear occurs thewalls III swing downwardly and outwear. The parts will not becomemisplaced even though there is no rotary mud pressure due to thepresence of the compression spring I32. The packing may be convenientlyreplaced by loosening the nuts H35, removing the gooseneck 90, and thenremoving the packing assembly. It is unnecessary to disturb any otherparts of the de vice. If desired, the grease nipples I31 and I38 may beremoved and the stuffing box housing lifted upwardly through the opening95. In this way the packing parts may be very easily removed andreplaced. At this time free access is had to the wash pipe and the washpipe may be disconnected from the spindle 4 3 by removing the nuts fromthe studs 88 and lifted upwardly through the opening 95.

In the alternative form of packing all parts are of the sameconstruction and the same numerals are applied except as follows. Thelower end of the stufling box housing 9? is opened and is provided withinternal threads E56 to receive a threaded gland l5! which is screwedupwardly around the wash pipe 85. Packing rings- I53 are placed in theupper part of the packing chamber W9 and a lantern. i5 3 is placed inthe packing chamber below the rings of packing 553. This lanternprovides a grease pocket 555 to which grease is supplied through apassage i536 formed in the stufling box housing 9?, there being a greasenipple I51 threaded into the passage 8%. Placed below the lantern i5 5are packing rings l5 which are engaged by the upper end of the glandI55. By screwing upwardly on the gland i at the packing is compressedand the gland may be locked in a desired position by means of a lock nutHit. In this form of our invention the pressure is not automaticallyapplied to the packing but must be manually applied by first looseningthe lock nut 56 and thereafter screwing the gland Hit in an upwarddirection. This type of construction, however, has the other advantagesof the general stufling box arrangement.

We claim as our invention:

1. In a swivel of the class described, the combination of a bodycomprising upper and lower separable parts; a spindle extending axiallythrough said body and rotatably supported exclusively by said lowerpart; lower spacing bearings carried by said spindle and engaging saidupper part, said spindle and said bearing means being removabledownwardly from said upper part when said upper and lower parts areseparated; and an upper bearing carried by said upper part and engagingsaid spindle, said upper bearing being removable upwardly from saidupper part.

2. In a swivel of the class described, the combination of: a bodycomprising upper and lower separable parts; a spindle extending axiallythrough said body and rotatably supported exclusively by said lowerpart; a hold-down bearing carried by-said spindle and engaging a lowerface of said upper part; a lower radial bearing carried by said spindleand engaging said upper part; and an upper radial bearing carried bysaid upper part and engaging said spindle, said spindle, said hold-downbearing, and said lower radial bearing being removable downwardly fromsaid upper part when said parts are separated. and said upper radialbearing being removable upwardly from said upper part.

3. In a swivel of the class described, the combination of a two partbody comprising upper and lower separable parts; a spindle extendingwardly, thus automatically compensating for the axially through saidparts; a thrust bearing carried within said lower part; a flange portionon said'spindle and carried by said thrust bearing whereby said spindleis rotatably supported by said lower part; a hold-down bearing carriedon said flange-portion and engaging a lower face of said upper part; alower radial bearing carried by said spindle and engaging an innerannular wall of said upper part; and an upper radial bearing carried bysaid upper part and engaging said spindle, said spindle, said hold-downbearing and said lower radial bearing being removable downwardly fromsaid upper part and said upper radial bearing being removable upwardlyfrom said upper part.

4. In a swivel of the class described, the combination of a two partbody comprising upper and lower separable parts, said lower part havingwalls forming an oil chamber; a thrust bearing within said chamber; aspindle-extending axially through said body and having a flange portionengaging said thrust bearing whereby said spindle is rotatably supportedsolely by said lower part; and walls forming sediment pockets in thelower wall of said chamber and positioned radially outward from saidthrust bearing, said sediment pockets being accessible for cleaning whensaid parts are separated.

5. In a swivel of the class described, the combination of a two partbody comprising upper and lower separable parts, said lower part havingwalls forming an oil chamber; a thrust bearing within said chamber; aspindle extending axially through said body and having a flange portionengaging said thrust bearing whereby said spindle is rotatably supportedsolely by said lower part; Walls forming sediment pockets in the lowerwall of said chamber and positioned radially outward from said thrustbearing, said sediment pockets being accessible for cleaning when saidparts are separated; and sealing means between said lower part and saidspindle below said oil chamber.

6. In a swivel of the class described, the combination of: a spindlerotatably supported in a stationary body and projecting upwardlytherefrom; a wash pipe carried on the upper end of said spindle androtatable therewith; a bridge comprising a lower plate supported by saidbody and an upper ring spaced from said lower plate by a plurality oflegs, said ring supporting a gooseneck for delivering fluid into saidwash pipe; and a packing housing surrounding said wash pipe and having aflange confined between said ring and said gooseneck for the supportthereof,

said packing housing extending downwardly from said upper ring and beingexposed to the air for cooling.

'7. In a swivel. of the class described, the combination of a spindlerotatably supported in a stationary body and projecting upwardlytherefrom; a wash pipe carried on the upper end of said spindle androtatable therewith; a bridge comprising a lower plate supported by saidbody and including sealing means engaging said spindle to seal the spacebetween said spindle and said body, and an upper ring spaced from saidlower plate by a plurality of legs, said ring supporting a gooseneck fordelivering fluid into said wash pipe; and a packing housing surroundingsaid wash pipe and having a flange confined between said ring and saidgooseneck for the support thereof, said packing housing extendingdownwardly from said upper ring and being exposed to the air forcooling.

8. In a rotary swivel, the combination of: an

upper body section having an opening, a lower shoulder near the lowerpart thereof, and an upper shoulder near the upper end thereof; a lowerbody section adapted to be secured to said upper body section andproviding a chamber; a rotatable spindle extending into said opening andsaid chamber; a thrust bearing in said chamber for taking the thrust ofsaid spindle; and upper and lower radial bearings for said spindle andbeing respectively in engagement with said lower and upper shoulders.

9. In a rotary swivel, the combination of: an upper body section havingan opening, a lower shoulder near the lower part thereof, and an uppershoulder near the upper end thereof; a lower body section adapted to besecured to said upper body section and providing a chamber; a rotatablespindle extending into said opening and said chamber; a thrust bearingin said chamber for taking the thrust of said spindle; upper and lowerradial bearings for said spi-ndle and being respectively in engagementwith said lower and upper shoulders; and a hold-downzibearihg for saidspindle positioned between said thrust hearing and said radial bearings.

10. In a rotary swivel, the combination of: a body providing a chamberhaving an upper elongated small cross-sectional portion and a lowerenlarged portion; a spindle extending into said chamber; a thrustbearing supported in said lower enlarged portion of said chamber forsupporting said spindle; and a pair of spaced radial bearings for saidspindle positioned in said upper small cross-sectional portion of saidchamber.

11. In a rotary swivel, the combination of: a bodyproviding a chamberhaving an upper elongated small cross-sectional portion and a lowerenlarged'portion; a spindle extending into said chamber; a thrustbearing supported in the lowermost part of said lower enlarged portionof said chamber for supporting said spindle; and

a pair of spaced radial bearings for said spindle positioned in saidupper small cross-sectional portion of said chamber.

12. In a rotary swivel, the combination of: a

body providing a chamber having an upper elongated small cross-sectionalportion and a lower enlarged portion; a spindle extending into saidchamber; a thrust bearing supported in said lower enlarged portion ofsaid chamber for supporting said spindle; a pair of spaced radialbearings for said spindle positioned in said upper small cross-sectionalportion of said chamber;- and a hold-down bearing for said spindlepositioned between said upper and lower portions of said chamber.

13. A combination ,as defined by claim 12 in which said spindle has ashoulder of larger crosssectional size than said upper portion of saidchamber, and which is engaged; by said thrust and hold-down bearings.

14. In a swivel of the class described, the combination of: a spindlerotatablysupported in a' stationary body and projecting upwardlytherefrom; a wash pipe carried on the upper end of said spindle androtatable therewith; a bridge supported by said body and having asupporting wall spaced above said body; a gooseneck for delivering fluidinto said wash pipe, supported by said supporting wall; and a packinghousing surrounding said wash pipe and having a flange confined betweensaid supporting wall and said gooseneck for the support thereof.

WILLIAM DAVIDSON. GUGLIELMO TREMOLADA.

